Three-gun turret: Inside the heart of Big Mo

The narrow, steep ladder leading to a small hatch entry forebodes danger. And the dense, steel-encased room, filled with aging machines and fixtures, hints a warp in time.

No, this is not a set of an action thriller film. This is the deck of one of three, three-gun turrets aboard the historic USS Missouri.

“This was where most of the action happened,” said Rich Costick, a Vietnam war veteran who volunteers at the re-moored battleship at Ford Island. “The fire power unleashed in these turrets was exceptional.”

For the unconvinced, consider these: The turrets are each powered with nine 16-inch, 50-caliber guns. Each gun is capable of firing 2,700-pound armor-piercing shells to a target as far as 46,000 yards or 23 miles away.

“The shell is about the same size and weight as a Volkswagen (Beetle),” Costick said, adding that the firing precision of its guns makes the 66 year-old battleship legendary. “The 23-mile range made the guns fierce but the accuracy made them deadly.”

With a highly coordinated crew inside the turrets able to fire two rounds of ammunition from each gun, the USS Missouri provided direct and continuous artillery support to the invasion landings at Iwo Jima in 1945 and protection to aircraft carriers in Operation: Desert Storm in the 1990s.

Firing a gun turret, however, was not done in random. The turrets were not manned by trigger-happy officers, either. Each fired round was executed through a complex and precise coordination of an estimated 100 crewmen positioned in the turret’s six mechanized floors.

The guns are loaded with a projectile brought up from one of the ammunition handling rooms below on a mechanical hoist. A turret officer specifies the type of projectile to be loaded: Armor piercing (AP) or high capacity (HP). The 2,700 pound AP round is a conventional projectile that was used against other ships or hardened concrete targets. The other, an HC, round weighs lighter at 1,900 pounds and was used for shore bombardment.

HATCHED UP. The turret consists of hatches leading to one of six specialized floors.

Once a projectile is selected, it comes up onto a hinged cradle which, when lowered, brings the projectile on the level of each gun’s breech. A hydraulic rammer pushes the projectile up into the gun, and then retracts to ready itself for another loading. A crewman opens the powder door revealing three powder bags that were brought up from the powder handling room below deck on another hoist, similar to a dumb-waiter. The three powder bags are pulled down onto the cradle with the hydraulic rammer pushing them up into the gun. When the rammer retracts, the powder door is opened again and three more powder bags are pulled down for the rammer to push up again into the gun. The cradle is raised back to vertical onto a projected target. The gun captain closes the breech door, inserts the primer cartridge, then turns the barrel switch to “Ready” mode that prompts a crew member at the fire director room above to pull the trigger and fire the projectile into its target.

“It takes about 90 seconds from the time (the projectile) leaves the barrel to reach its target,” Costick explained. “In all honesty, (the USS Missouri) can fire 27 rounds (of ammunition) in the air at any given time. That’s a lot of hurt.”

One of a few hand-painted maps inside Turret 2. Apart from Japan, maps of Australia and the Korean peninsula adorn the turret's steel walls.

Despite being a critical feature of the USS Missouri, the turrets are not actually attached to the ship. According to Costick, if the ship were to capsize, the turrets would fall out. “They just sit on top of rollers and only their weight, which is about 1,700 tons without any ammunition, keeps them stable on the ship.” The turrets are mobile though. They can rotate through about 300 degrees range of motion at about four degrees per second.

Commissioned in 1944, the USS Missouri was the final battleship completed by the United States. Nicknamed Mighty Mo or Big Mo, it went into action during World War II, the Korean War and the Persian Gulf War before its final decommissioning.

According to Costick, Big Mo sailed with a crew between 2,700 to 3,000 men aboard, including 132 officers and 53 Marines during World War II and the Korean War. After its modernization in 1986, that number was reduced to about 1,500 men, which included 65 officers and a detachment of 53 Marines.

CUP OF JO IN BIG MO. Costick describes the coffee machine inside the turrets as the most important.

Inside Big Mo’s Turret 2, signs of its active past remain. Hand-painted maps of the Far East such as Japan, Korea, and Australia, adorn the steel walls giving away the destinations it first sailed to. An intercom phone hangs in between hatches that lead to the turret’s gun chambers with a sign above it that reads, Do not discuss classified information over this phone. Two metal bar stools with torn leather upholstery make up most, if not all, of the turret’s seating fixtures. And six mugs of varying designs hang haphazardly on top of a long, steel-plated coffee machine. “That was actually the most important machine of the turret,” Costick quipped with a grin.

While the turrets show signs of disuse and the battleship’s future remains uncertain, Big Mo is still sea-worthy and ready for battle. “People like to think (USS Missouri) is a historic artifact. We can’t assume that designation because of the modernization that took place in the mid-1980s,” Costick explains. “Technically, if the Navy wants to invest much time and money in getting the engines and weapons running, (USS) Missouri can be reactivated for combat again.”